For more than 50 years, people have been watching TV at night, often prior to going to sleep. This has only expanded in the era of devices, especially with the introduction of Apple’s iOS devices along with those of its competitors.

Worse, these devices, which tend to be set to a bright level, are now directly in front of the user, often less than two feet away at the time before use.

With that in mind, Dr. Raymond Soneira of DisplayMate has done an extended study and breakdown of Night Shift, Apple’s light shifting technology that’s recently made its way to the iOS.

With the rapidly increasing use of these displays, particularly at night, vision and sleep researchers discovered that watching a display at night can not only make it harder to fall asleep (up to 1.5 hours longer), but then the quality of sleep during the night is also reduced, and it carries over into the following morning with reduced alertness. So improperly watching a display at night can lead to sleep disorders, which in turn can lead to a wide variety of serious psychological and medical issues, including evidence for increased heart attacks and a higher risk of some cancers, which have been documented in sleep research studies.

That being said, DisplayMate has a full breakdown and study of Night Shift. While not a review, it does offer recommendations for both users and technology manufacturers alike,

The piece is extensive, dives into spectrum analysis as well as human reactions to different light spectrum while trying to fall asleep and if you’ve ever wondered about the idea of disconnecting from your devices before bed and how your devices might affect your sleep, take a gander.